Isolation and characterization of the promoter of RGG1 using Agrobacterium-mediated transient assay

The heterotrimeric G protein complex, comprising of Gα , Gβ , and Gγ subunits, is an evolutionarily conservedsignaling molecular machine which transmits signals from transmembrane receptors to downstream target proteins. Now-a-days their functions in plant stress-signalling have been reported. Here we have isolated the promoter of rice G-protein γ subunit 1(RGG1) from rice genomic DNA. In silico analysis revealed that promoter of RGG1 contained a TATA, a CAAT motif and also harbors some important stress and hormone associated cis regulatory elements, including E-box, GAAAAA, GATA-box,CACATG, CCGTCC and CCACC. Functional analyses were performed by Agrobacterium-mediated transient assay in tobacco leaves. Very high level of GUS activity was observed in agro infiltrated tobacco leaves by the construct carrying the RGG1 promoter::GUS, subjected to abiotic stress and exogenous hormonal treatments. Stress-inducible nature of RGG1 promoter opens possibility for the study of the gene regulation under stress condition. Therefore, the result may be useful in the field of agriculture and biotechnology.